患病: 生病的: 感觉不舒服: 我病了.I’m now. 上个星期我姐姐病倒了. , my sister . Yesterday Li Ming (生病), so he didn’t come to school. 查看更多

 

题目列表(包括答案和解析)

明同学利用A、B两物体、砝码、泡沫等器材探究“压力的作用效果与什么因素有关”的实验.如图

(1)实验中,小明是通过观察   ▲   来比较压力作用效果的.
(2)比较甲、乙两图所示实验,能够得到的结论是:       ▲     
(3)若要探究“压力的作用效果与受力面积大小的关系”,应通过比较图   ▲  
所示实验.
(4)小华同学实验时将物体B沿竖直方向切成大小不同的两块,如图丁所示.他发现
它们对泡沫的压力作用效果相同,由此他得出的结论是:压力作用效果与受力面积无关.你认为他在探究过程中存在的问题是:          ▲            .

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  1.Peter把他所有的家产都送了人,出家为僧。

  Peter _____ _____ _____ _______________ _____ and became a monk.

  2.你就不能破一次例吗?

  Can’t you _____ _____ _____ just this one time?

  3.他无法控制怒气。

  He couldn't _____ _____ _____ _____.

  4.那么,你必须和其他人一样排队等候。

  Well, you have to _____ _____ _____ like everyone else.

  5.因为这些压力,现在我不能更多的把这一行当视为艺术,而仅仅是一种谋生手段。

  This isn't like doing artwork for me anymore because of the stress. Now I'm just trying to _____ _____ _____.

  6.但是还有其它大量的迹象表明,一切都出了问题。

  There are _____ _____ other signs that all is not well.

  7.我有来自世界各地的邮票。I have stamps from _____ _____ _____ _____.

  8.在我生病期间,我没有花多少零用钱。

  While I was sick, I hadn’t spent any of my _____ _____.

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补全对话(共5分)

  从方框内选择恰当的句子完成下面的对话。(共5分,每小题1分)

A. A table for two?

B. What can I do for you?

C. My I take your order now?

D. Excuse me. Could we have some coffee, please?

E. This way, please.

F. Anything else?

G. What would you like to drink?

  Waiter: Good morning, madam.

  Gina: Good morning.

  Waiter: 1._____________

  Gina: Yes. Can we have table by the window?

  Waiter: OK. 2. _____________

  ( At the table )

  Waiter: Here's the menu. 3.__________

  Gina: Yes. We'd like chicken with potatoes, beef with onions and some rice.

  Waiter: 4.__________

  Gina: Orange juice.

  Waiter: 5.________

  Gina: No, that's all. Thank you.

 

 

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 缺词填空。(每空一词)(10分)
 1. Can you give me some __________(建议) about learning math?
 2. Kate often feels________(紧张不安的) when she talks to me.
3. I like history,but I don’t like__________(地理).
4. There are many_______(语言)in the world. Most of them aren’t used widely.
 5. Do you know the________(长)of the Yellow River?
 6. Do you like your trip? Is it                  (令人愉快的).
 7. The girl with long hair is the__________(苗条的)of the three.
 8. Liu Xiang and Yao Ming are both my h_________.Do you agree with me?
 9. We don’t know this song very well because it’s u________.
10. He is________ (1ike to give money or things to others)to his friends.

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(10分)植物具有向重力生长的特性,下列是研究根向重力生长机理的两个实验。
实验一:将空白琼脂和含EDTA的琼脂做成帽状,分别套在甲、乙两组玉米胚根的根冠外(示意图如下)。提示:EDTA的作用是去除与其临接部位的 Ca2+

将胚根水平放置培养一定时间后,观察到甲组胚根向重力(下)生长,乙组胚根水平生长。根据上述实验结果,得出实验结论:                               
  实验二:水平放置的胚根弯曲向下生长,与根冠近地侧的Ca2+浓度明显高于远地侧有关。研究表明,根总是朝着Ca 2+浓度高的方向弯曲生长。为验证这一结论,有人设计了下列实验方案。请根据提供的实验材料和用具,写出第二步及以后的实验步骤和实验结果,并回答问题。
(1)实验材料和用具:胚根等长的萌发玉米种子,空白琼脂帽,含EDTA的琼脂帽,上面部分含Ca2+的琼脂帽(水平方向),培养皿等。
(2)实验步骤:
  第一步:取若干个培养皿,在每个培养皿中放置适量的萌发玉米种子,按实验一中乙组的方法处理胚根一定时间后,移去根冠外的琼脂帽。然后将培养皿平均分成两组,编号为 A组、B 组。 
  第二步:                                                            
  第三步:                                                            
(3)实验结果:                                                         
(4)科学家进一步证实,根冠中生长素的分布受Ca2+浓度影响,当胚根水平放置时,重力诱导Ca2+向根冠下侧移动,导致近地侧的生长素浓度比远地侧高。请分析胚根的生长素分布与向重力生长的关系:                                  

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